Process of blanching wood or like materials



Patented Nov; l, 1938 PROCESS OF BLANCENG WOOD R LIKE MATERIALS LawrenceR. Van Allen, Chicago, ill.

No Drawing. Application May 5, 1934, Serial No. 724,218

1% Claims.

This invention relates to a process of blanching wood and other solidfibrous material.

A principal object of the invention is the provision of a processforblanching or bleaching the surface of veneer, plywood, solid wood, orwood substitutesuch as paper, fibreboard, cellulose board and the like.

Another important objectof the invention is the provision of a processin whicha differential treatment of the surface of the material may becarried on over selectively determined areas of any size or contour togive to them a distinctive appearance as to coloring or shading ascompared with surrounding or adjacent areas.

A further important object of the invention is the provision of aprocess which permits of this blanching or bleaching treatment overselected areas by persons not particularly skilledln the art, and at agreatly reduced cost.

Numerous other objects and advantages of the invention will be apparentas it is better understood from the following description.

The process embodying my invention is or may be carried out in asuccession of treatments which may follow each other immediately or maybe, timely separated. In the first step of the process, the surface tobe blanched is coated with a layer or blanket of viscous material. Thisprepares the wood or other material underneath the blanket for thereaction with the bleaching agent subsequently to be applied, and alsoserves to confine the action ofthe bleaching agent to the particulararea being treated. The next step of the treatment consists in theapplication of the activator or neutralizer which-primarily consists ofa strong bleaching agent, several of these being available on themarket.

The blanket material, which is applied with a brush, sponge or the liketo the surface to be treated, consists of an adhesive and a carrier forthe same, and it has sufilcient body consistency so that it will not runor spread beyond the surface or area portion to be treated. Glycerine orcasein may be employed as the adhesive ingredient while the carrier maybe composed of kieselguhr, infusorial earth, magnesium carbonate,aluminum sulphate, or other suitable material.

The adhesive and the carrier give to the material a thick syrupy bodywhich permits it to be spread or stencilled on a particular surface orarea within sharply defined boundary lines and to this adhesive andcarrier is added a sub stance which imparts acidity, such as sulphonicor acetic acid, or which imparts alkalinity, such as caustic soda,ammonia, etc.- As has been stated this coating or blanket material is ofsuch consistency that when spread over a selected area portion to betreated there is no danger of its running or spreading to adjacent areasand affecting the finish on such areas.

After this blanket has been placed in position for a predeterminedlength of time, which period varies with different woods and with thedegree of bleaching action to be accomplished, aneu' l0 tralizer oractivator is applied to constitute a finishing coat. This finishing coatcarries out the bleaching action and any of the well known bleaches maybe used, such as peroxide of hydrogen, potassium persulphate, potassiumperlo borate, ammonia borate, etc. Danger of, harm to the finish ofadjacent surfaces is negligible because should the bleaching agent flowbeyond the border of the surface being treated, it may be readily wipedoff and leave the surface unmarred due to its slow bleaching action.

It is possible by proper application of the blanket and proper selectionof the activator or finishing coating; to be subsequently applied, 'toblanch or bleach any fibrous material. Not only solid woods may betreated by nLv special process, but veneers, which have become streakedor are undesirably colored, may be refinished so that their appearanceis entirely changed.

Where it is desired to refinish the entire surface without producing adistinctive appearance to a selected portion thereof, the blanketmaterial may be diluted with ammonia, or other catalytic agent, andwater. This pre-treated fibrous material may then be finished by the 5application of a strong bleaching agent (where peroxide is used as ableaching agent, ammonia or some other catalytic agent may be employedeffectively to release the oxygen upon its application) e It has alsobeen found that the blanket or initial coating may be formed of sulphitepulp, or like material, pressed into sheet form and dried to permit itto be cut into patterns, shapes, stencils or designs, which are placedon the surfaces to be blanched or bleached in localized or desiredareas. This cellulose blanket is impregnated or coated with a substanceof active catalytic reaction to desired bleaching agents.

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and it will beapparent that various changes may be made in the steps and their orderof accomplishment of the process described without departing from thespirit and scope of the invention or sacrificing all of its materialadvantages, the process hereinabove described being merely a preferredembodiment thereof.

I claim:

1. Theprocessoftreatingadesired limitedarea of a compact fibrousmaterial, comprising applying to such limited area only a blanket ofviscous preparatory material, and subsequently applying to said limitedarea an agent adapted to bleach the fibrous material.

2. The process of treating compact fibrous material, comprising applyingto a selected surface to be treated a coating of viscous preparatorymaterial, and subsequently applying to said surface an agent adapted tobleach said fibrous material,

said preparatory material including a catalytic agent which will speedthe action of said bleaching agent.

3. The process of preparing compact fibrous material for bleaching,comprising applying to a selected surface of the material to be treateda viscous coating of preparatory material comprising an inorganicmineral carrier and an adhesive for vegetable materials.

4. The process of treating a desired limited area of a compact fibrousmaterial, comprising applying to such limited area only a blanket ofviscous preparatory-material including glycerine and a soluble carriertherefor, and subsequently applying to said limited area an agentadapted to bleach the fibrous material.

5. The process of treating a desired limited area of a compact fibrousmaterial, comprising applying to such limited area only a blanket ofviscous preparatory material including casein and a soluble carriertherefor, and subsequently applying to said limited area an agentadapted to bleach the fibrous material.

6. The process of treating compact fibrous material, comprising applyingto a selected surface to be treated a coating of viscous materialincluding glycerine and a suitable carrier therefor, and subsequentlyapplying to said surface an agent adapted to bleach said fibrousmaterial, said preparatory material including a catalytic agent whichwill speed the action of said bleaching agent.

'7. The processof treating'compact fibrous material, comprising applyingto a selected surface to be treated a coating of viscous materialincluding casein and a suitable carrier therefor, and subsequentlyapplying to said surface an agent arsaaos adapted to bleach said fibrousmaterial, said preparatory material including a catalytic agent whichwill speed the action of said bleaching a ent.

- 8. The process of preparing compact, fibrous material for bleaching,comprising applying to a selected surface to be treated a viscouscoating of preparatory material having an alkaline reactionv andincluding an inorganic soluble mineral carrier and a vegetable adhesive.

9. The process of preparing compact fibrous material for bleaching,comprising applying to a selected surface to be treated a viscouscoating of preparatory material having an acid reaction and including aninorganic mineral carrier and an adhesive for vegetable materials.

10. The process of preparing compact fibrous material for bleaching,comprising applying to a desired limited surface thereof a viscouscoating of preparatory material comprising glycerine and an inorganicmineral carrier.

11. The process of preparing compact fibrous material for bleaching,comprising applying to a desired limited surface thereof a viscouscoating of preparatory material comprising casein and an inorganicmineral carrier.

12. The process of preparing compact fibrous material for bleaching,comprising applying to a selected surface to be treated a viscouscoating of preparatory material including sulphonic acid, an inorganicmineral carrier and an adhesive for vegetable materials.

13. The process of preparing compact fibrous material for bleaching,comprising applying to a selected surface to be treated a viscouscoating of preparatory material including acetic acid, an inorganicmineral carrier and an adhesive for vegetable materials.

14. The process of bleaching a desired limited area of a compact fibrousmaterial, comprising applying to the surface of said fibrous material asheet of cellulose cut to the desired shape, and subsequently applyingto said sheet of cellulose a bleaching agent, said sheet of cellulosebeing impregnated with a preparatory material comprising an inorganicmineral carrier and an adhesive for vegetable materials, and saidbleaching agent being adapted to soak through said sheet of celluloseand act with said preparatory material upon said desired limited area ofthe compact fibrous material.

LAWRENCE R. VAN ALLEN.

